CHARGING SYSTEM, Diagnostic DTC:P1550, P1551, P1552

DTC Code DTC Name
P1550 Battery Current Sensor Circuit
P1551 Battery Current Sensor Circuit Low
P1552 Battery Current Sensor Circuit High

DESCRIPTION

A01M1T3E02

The battery current sensor assembly installed on the negative (-) battery terminal detects the amount of current supplied from the generator.

The battery current sensor assembly changes current to voltage (at the negative (-) battery terminal) and sends it to the ECM. The ECM controls the voltage of the generator based on the signals from the battery current sensor assembly.

DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate Memory Note
P1550 Battery Current Sensor Circuit

Difference between the maximum and minimum current values of the battery current sensor is less than 1 A for 10 seconds or more with the ignition switch ON

(1 trip detection logic)

  • Battery current sensor assembly

  • Wire harness or connector

  • ECM

 Charge warning light does not come on DTC stored w/ Battery Current Sensor
P1551 Battery Current Sensor Circuit Low

Battery current sensor output value is less than 0.2 V for 0.5 seconds or more with the ignition switch ON

(1 trip detection logic)

  • Battery current sensor assembly

  • Wire harness or connector

  • ECM

 Charge warning light does not come on DTC stored w/ Battery Current Sensor
P1552 Battery Current Sensor Circuit High

Battery current sensor output value is higher than 4.8 V for 0.5 seconds or more with the ignition switch ON

(1 trip detection logic)

  • Battery current sensor assembly

  • Wire harness or connector

  • ECM

 Charge warning light does not come on DTC stored w/ Battery Current Sensor

WIRING DIAGRAM

Refer to DTC P0516.

Click here

CAUTION / NOTICE / HINT

Note

Before replacing the ECM, refer to Service Bulletin.

PROCEDURE


  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P1550, P1551 OR P1552)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    5. Read the DTCs.


      Powertrain > Engine and ECT > Trouble Codes
      Result
      Result Proceed to
      DTC P1550, P1551 or P1552 is output. A
      DTC P1550, P1551 or P1552 and other DTCs are output. B

      Tech Tips

      If any DTCs other than P1550, P1551 or P1552 are output, troubleshoot those DTCs first.


    B

    GO TO DTC CHART Click here

    A

  2. READ VALUE USING GTS (BATTERY CURRENT)


    1. Turn all of the electrical systems (headlights, blower motor, rear defogger, etc.) off.

    2. Connect the GTS to the DLC3.

    3. Turn the ignition switch to ON.

    4. Turn the GTS on.

    5. Enter the following menus: Powertrain / Engine and ECT / Data List / Battery Current.

    6. According to the display on the GTS, read the Data List.


      Powertrain > Engine and ECT
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Battery Current Battery current Min.: -125 A, Max.: 124.9 A

      Changes according to alternator output:

      While driving after engine warmed up

      		 If the result is not as specified, a malfunction of the charging control system is suspected.

      Powertrain > Engine and ECT > Data List
      Tester Display
      Battery Current
      Result
      Result Proceed to
      Battery current is maintained at 0 A, or fluctuates by +/- 1 A or less between -100 and 100 A. A
      Battery current fluctuates between -20 and 0 A. B

    B

    CHECK FOR INTERMITTENT PROBLEMS

    A

  3. INSPECT BATTERY CURRENT SENSOR ASSEMBLY


    1. Inspect the battery current sensor assembly.

      Click here

      Result
      Result Proceed to
      OK (for Sedan) A
      OK (except Sedan) B
      NG C

    B

    CHECK HARNESS AND CONNECTOR (ECM - BATTERY CURRENT SENSOR ASSEMBLY) Click here

    C

    REPLACE BATTERY CURRENT SENSOR ASSEMBLY Click here

    A

  4. CHECK HARNESS AND CONNECTOR (ECM - BATTERY CURRENT SENSOR ASSEMBLY)


    1. Disconnect the B186 ECM connector.

    2. Disconnect the B232 battery current sensor assembly connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      B186-87 (THB) - B232-1 (THB) Always Below 1 Ω
      B186-118 (EIB) - B232-4 (E2) Always Below 1 Ω
      B186-117 (VCIB) - B232-2 (VC5) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      B186-87 (THB) or B232-1 (THB) - Body ground Always 10 kΩ or higher
      B186-118 (EIB) or B232-4 (E2) - Body ground Always 10 kΩ or higher
      B186-117 (VCIB) or B232-2 (VC5) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE ECM Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  5. CHECK HARNESS AND CONNECTOR (ECM - BATTERY CURRENT SENSOR ASSEMBLY)


    1. Disconnect the B186 ECM connector.

    2. Disconnect the A164 battery current sensor assembly connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      B186-87 (THB) - A164-1 (THB) Always Below 1 Ω
      B186-118 (EIB) - A164-4 (E2) Always Below 1 Ω
      B186-117 (VCIB) - A164-2 (VC5) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      B186-87 (THB) or A164-1 (THB) - Body ground Always 10 kΩ or higher
      B186-118 (EIB) or A164-4 (E2) - Body ground Always 10 kΩ or higher
      B186-117 (VCIB) or A164-2 (VC5) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR